Porphyrins lie at the heart of many biological energy metabolism systems. Synthetic model systems incorporating prophyrins provide incisive tools for investigating detailed mechanisms of such metabolic processes. 252Cf mass spectrometry is invaluable as an aid to characterizing synthetic porphyrins. A manuscript describing the 252Cf plasma desorption mass spectrometry of more than 100 porphyrins and porphyrin complexes has been published in Analytical Chemistry and a second manuscript is in the planning stages. We are currently evaluating the utility of electrospray ionization and matrix-assisted laser desorption mass spectrometry as tools for the analysis of porphyrin complexes.